A detailed experiment investigating how long to steep immersion cold brew, with both numerical and qualitative results.
I would add that it’s just based on her personal taste. She seems to have a pretty good pallet, but it’s hard to say how many would agree with her assessment.
True. It also matters what you’re doing with it. Are you adding cream and sugar. I like a cold brew and tonic and to get the cold brew to stand up to the tonic I brew between 24 and 36 hours. If I’m sipping on it as is I usually only let it go overnight.
I’ll also do batches where I brew it with only enough hot water to let the coffee bloom, then drop ice water on it and let it sit overnight. That’s been my favorite so far.